1. Field of the Invention
The present invention relates to an optical disc driver, and more particularly to an optical disc driver and a data recording method for the optical disc driver which can reduce a data recording time by separating a data reproducing process from a data recording process in recording data and reducing the number of seeks of a servo.
Also, the present invention relates to an optical disc driver and a data recording method for the optical disc driver which can reduce the number of seeks of a servo and thus reduce a data recording time by performing a data reproduction only with respect to the first data recording command and the last data recording command, and performing an encoding of respective error correction code (ECC) blocks with respect to sequential intermediate data recording commands without performing the data reproduction in the event that data recording commands which deviate from the boundaries of the ECC blocks are sequentially received.
2. Description of the Related Art
Generally, an optical recording medium is classified into three types depending on whether or not data can be repeatedly recorded on the medium: a read only memory (ROM) type, a write once read many (WORM) type on which data can be written only once, and a rewritable type on which data can be repeatedly written.
As a repeatedly rewritable disk, there exist a rewritable compact disc (CD-RW) and a rewritable digital versatile disc (DVD-RAM).
Meanwhile, a DVD-RAM drive reproduces user data recorded on a disc, or records the user data transmitted from a host on the disc in accordance with a command of the host. At this time, the host transmits the command that includes a command code, a recording position, and the number of recording sectors.
The DVD-RAM drive analyzes the received command, and if it is analyzed that the received command is a data reproduction command, it reproduces the data from the disc, and transmits the reproduced data to the host. If it is analyzed that the received command is a data recording command, the DVD-RAM drive transmits to the host a response signal for notifying the reception of the command, and records the data on the disc as long as the time permitted.
Accordingly, in case of the data reproduction, the host transmits the next command to the drive after receiving all the data from the drive. In case of the data recording, the host transmits all the recorded data to the drive, and if the response signal is received from the drive, it transmits the next command.
Meanwhile, in case that the data recording command for the sequential user blocks is received, if the next data recording command is received after the completion of the data recording, a pickup may pass a portion where the next command is to be performed after performing the current command. In this case, the servo should search again and record the portion to be recorded by performing a back jump. As a result, since the servo should perform the back jump whenever the data recording command is received, the recording performance greatly deteriorates.
FIG. 1 is a view conceptually illustrating the data storage state of a general optical disc.
In FIG. 1, ‘A−16’, ‘A’, ‘A+16’, ‘A+32’, and ‘a’ denote addresses of the optical disc. The disc is divided into virtual boundaries for addresses corresponding to “0” and multiples of “16” after being manufactured. These boundaries are called ECC block boundaries. An ECC block is a unit of the data process when the data is recorded on the disc.
For instance, if a command to reproduce data of an ‘x’ portion that starts from the ‘a’ address in FIG. 1 is received from the host, the data to be transmitted to the host is only the data of the ‘x’ portion, but the optical disc driver should read out the data of the whole ‘X’ portion including ‘y1’, ‘x’, and ‘y2’ portions to reproduce the data of the ‘x’ portion.
Also, in case of recording the data on the disc, if a command to recording the data on the ‘x’ portion of the disc is received, the optical disc driver should encode and record in the unit of an ECC block not only the data of the ‘x’ portion but also the data of the ‘y1’ and ‘y2’ portions.
As described above, the DVD-RAM drive processes the data in the unit of an ECC block when recording or reproducing the data. However, the host does not necessarily command the recording or reproduction in the unit of an ECC block. At this time, the drive, which has received the data recording command in the unit of a sector from the host, first reproduces the ECC block that includes the sector, inserts the user data transferred from the host in a determined position in the ECC block, and then performs the data recording to match the ECC block by encoding the data. Otherwise, the data of other sectors existing in the ECC block is damaged.
However, if the data recording commands that deviate from the ECC block boundaries are sequentially received, the above-described reproduction/recording operation should be repeated, and this greatly deteriorates the recording speed.